What the vulnerability does
01Description
The Maxi Blocks plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the `/wp-json/maxi-blocks/v1.0/style-card` REST API endpoint in all versions up to, and including, 2.1.9 due to insufficient input sanitization and output escaping of the `sc_styles` parameter. This makes it possible for authenticated attackers, with Author-level access and above, to inject arbitrary web scripts that execute on every page where the plugin's style card styles are loaded, including across the entire WordPress admin panel.
Explanation of Vulnerability in Simple Terms
02Summary
MaxiBlocks Builder versions up to 2.1.9 contain a stored cross-site scripting (XSS) vulnerability. An authenticated user with low privileges can inject malicious scripts that execute in the browsers of other site visitors, potentially compromising their sessions or stealing data. The vulnerability affects the entire site scope due to how the builder processes and stores user input.
What an attacker can do
03Attacker Capabilities
Inject malicious scripts that run in other users' browsers and steal their session data or perform actions on their behalf.
Potential impact on your site
04Site Impact
Visitors and admins may have their sessions hijacked or be redirected to malicious sites; stored malicious content persists until manually removed.
Conditions required to exploit
05Prerequisites
Attacker must have a low-privilege account on the site; no user interaction required from victims.
Key dates
06Disclosure timeline
May 2, 2026
CVE published
May 4, 2026
Record updated
